Description: The Challenger is a derivative of the Chieftain main battle tank modified to produce the Shir for Iran. After Iran's 1979 revolution, the Shir project was taken over by the British Army a redesigned as the Challenger. The Challenger replaced the Chieftain as the iron fists of the British Army. It features a more powerful engine, rated at 1,200 hp, and improved protection thanks to its Chobham armor.

The Challenger 2E is an enhanced version of Challenger 2 main battle tank optimized for the harshest environments providing outstanding firepower and mobility. The Challenger 2E main battle tank is powered by a Europack engine which provides 1,500 hp instead of the 1,200 hp of the CV12 engine. The hull and turret have been redesigned to minimize millimeter radar wave returns and the IR signature has been reduced increasing Challenger 2E survivability. Built-in auto diagnosis system and the use of Line Replaceable Unit have optimized maintainability and availability.